Yes. Eliminating or vastly reducing the head-on collisions caused by drivers drifting across the center line, and the rear-end collisions where they don't see the stopped or slow car ahead of them, are a huge win. I'd trade full self-driving for really effective lane departure warnings and auto-braking collision avoidance any day of the week. Next step (or included) would be reacting to red lights/stop signs if it appears that the driver is not stopping. Deal with those things well and you've eliminated the causes of most serious accidents.